1. Field of Invention
The invention relates to a tablet electronic device and, more particularly, to a tablet electronic device with a holding structure.
2. Related Art
A tablet personal computer (also called a tablet PC, a tablet, or slates for short) is a small and portable personal computer, and a touch screen is used as a main input device. The touch screen of the tablet PC allows a user to input information directly via built-in input modules, such as a handwriting recognition module, a virtual keyboard on the screen or a voice recognition module instead of a conventional keyboard and mouse. Furthermore, compared to a notebook, a personal digital assistant (PDA) and a smart phone, the lighter tablet PC has a larger screen is more convenient for the user.
The monitor size of the current tablet PC is usually between seven to twelve inches, and the tablet PC has three major types, a rotatable-type, a panel-type, and a multimulti-type. A rotatable-type tablet PC looks like a notebook, its processor and calculating elements are disposed under the keyboard or a base portion, and the user can rotate the screen for 180 degrees to cover the keyboard as a plane type. A panel-type tablet PC is usually configured with a touch screen and a stylus, and the calculating elements are disposed under the screen. It may also connect to an external keyboard or inserted to a docket to have more expanding functions. A multi-type tablet PC is similar to the rotatable-type tablet PC, and the difference is that the keyboard or the base portion is detachable. Thus, the multi-type tablet PC has the advantages of the rotatable-type tablet PC and the panel-type tablet PC.
However, no matter what type the tablet PC is, the user usually holds one side of the tablet PC with one hand and operates it with the other hand. While outdoors or traveling with environmental limitations, more chances for users are holding the tablet PC with one hand instead of two hands. FIG. 1 is a schematic diagram showing a conventional tablet PC, and a panel-type tablet PC is taken as an example. The conventional tablet PC 1 includes a touch panel 11, a battery pack 12 and other necessary electronic components which omitted herein.
As shown in FIG. 1, the casing of the conventional tablet PC 1 has a symmetrical panel structure without a holding portion, and thus the user is difficult to hold it. Further, the battery pack 12 is usually a thin-type battery which is larger but thin. As the heaviest electronic component of the tablet PC 1, the battery pack 12 is usually disposed at the back of the tablet PC 1 to keep a gravity center G at geometric center of the tablet PC 1.
Nowadays, the weight of the conventional tablet PC is reduced to relieve discomfort and tiredness of the user's hand when holding the tablet PC. However, since the casing of the tablet PC is usually a flat plate, it is not easy to be hold. Additionally, due to the larger screen, a distance between the gravity center G and the holding side 13 of the tablet PC 1 is far, this increases the difficulties in holding the tablet PC, too. In more detail, taking holding side as an axis, and the distance L is the arm of force, the arm L of force multiples the total weight of the tablet PC 1 and the battery pack 12 (which can be regarded as applying force on the gravity center G), a rotating torque T thus obtained is very large, this perplex users to hold the tablet PC for a long time with one hand, and the user even may drop down the table PC while operation by accident.